In mobile communications systems, such as cellular telephone networks, billing is conventionally carried out on a subscriber-by-subscriber basis. Herein, the term “subscriber” refers to the person authorised to access a mobile communications system, using a mobile station or a fixed station.
In a GSM system, when a subscriber utilises a mobile communications resource, such as conducting a voice call, sending a fax, retrieving voicemail messages, sending text messages, etc, a call detail record is produced in the network which is sent to a billing centre.
At the billing centre, the call detail records are logged on-line, and periodically transferred to an off-line billing system, for example on magnetic tapes. The call detail records are rated to attach a charge to each usage recorded in the call detail records. This charge depends on the type of service utilised, the length of a connection utilised, and may also depend on the particular type of subscription which the subscriber holds.
At the end of a billing period, for example at the end of each month, the rated call detail records are processed on a subscriber-by-subscriber basis to produce an individual bill for each subscriber.
However, this conventional method of billing implemented in the billing centre is not particularly convenient for customers having multiple subscribers utilising the mobile communications system. It can be difficult to manage costings for a group of subscribers when individual bills are separately received.
U.S. Pat. No. 4,979,207 proposes a cellular telephone billing system which processes call detail records of calls made by subscribers belonging to multiple-subscriber customers to produce bills. The call detail records are processed to attach a key identification number for each subscriber. The key identification number and a chosen associated information format are used to select a type of billing report required by the customer so that it may be provided during billing. However, this only provides a way to produce a desired format of billing report for a customer, and does not affect the charge made to a customer.